FDA approves first micro-device for glaucoma treatment

Glaukos Corp. has received FDA approval for its iStent Trabecular Micro-Bypass, This is the first glaucoma implant to be approved in the United States (U.S.). The iStent is indicated for use in conjunction with cataract surgery for the reduction of IOP in adult patients with mild to moderate open-angle glaucoma currently treated with ocular hypotensive medication.

The device falls under the category of micro invasive glaucoma surgery. The iStent is designed to create a bypass through the trabecular meshwork to Schlemm’s canal in order to improve aqueous outflow through the natural, physiologic pathway. The iStent is a 1-mm implant, made of non-ferromagnetic titanium, and is the smallest medical device known to be implanted into the human body. The iStent, a therapeutic device, is placed into Schlemm’s canal using an inserter and intra-operative gonioscopy.

The IDE pivotal study for iStent conducted by Glaukos was the first prospective, randomized U.S. IDE trial for a glaucoma device. The trial, conducted at 27 sites, enrolled 239 subjects with mild to moderate open-angle glaucoma and clinically significant cataract. Subjects were randomized 1:1 to either iStent in conjunction with cataract surgery, or cataract surgery alone. The results showed that 68 percent of subjects in the iStent treatment group (combined cataract and iStent implantation) met the primary endpoint of IOP ≤21 mmHg with no medications at 12 months.

Because iStent is implanted ab interno (from the inside), the procedure is conjunctiva-sparing and blebless. It also serves to preserve future therapeutic and surgical options for glaucoma patients. Glaukos has enrolled more than 4,000 patients worldwide in clinical studies evaluating iStent devices in open-angle glaucoma.

The most common adverse events included early postoperative corneal edema, BCVA loss of ≥ one line at or after the three-month visit, posterior capsular opacification, stent obstruction, early postop anterior chamber cells, and early post-op corneal abrasion. All adverse events had a rate of occurrence measured at 8 percent or less.